VulnerabilityPublished 6 May 2026Updated 8 May 2026

CVE-2026-43130: Linux kernel · iommu/vt-d: Flush dev-IOTLB only when PCIe device is accessible in scalable mode

Source GCVE Database

Not known to be exploited · CVSS 5.5 Medium.

Data as of 27 Oct 2026, 03:25 UTC

CVSS 3.1 base score

5.5Medium

How severe the flaw is on the 0–10 CVSS scale.

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Attack Vector: Local
Attack Complexity: Low
Privileges Required: Low
User Interaction: None
Scope: Unchanged
Confidentiality: None
Integrity: None
Availability: High

Bold values are the worst case: easiest to exploit or largest impact.

Attack Vector: Local: The vulnerable component is not bound to the network stack and the attacker’s path is via read/write/execute capabilities. Either: the attacker exploits the vulnerability by accessing the target system locally (e.g., keyboard, console), or remotely (e.g., SSH); or the attacker relies on User Interaction by another person to perform actions required to exploit the vulnerability (e.g., tricking a legitimate user into opening a malicious document).
Attack Complexity: Low: Specialized access conditions or extenuating circumstances do not exist. An attacker can expect repeatable success against the vulnerable component.
Privileges Required: Low: The attacker is authorized with (i.e., requires) privileges that provide basic user capabilities that could normally affect only settings and files owned by a user. Alternatively, an attacker with Low privileges may have the ability to cause an impact only to non-sensitive resources.
User Interaction: None: The vulnerable system can be exploited without any interaction from any user.
Scope: Unchanged: An exploited vulnerability can only affect resources managed by the same security authority. In this case, the vulnerable component and the impacted component are either the same, or both are managed by the same security authority.
Confidentiality: None: There is no loss of confidentiality within the impacted component.
Integrity: None: There is no loss of integrity within the impacted component.
Availability: High: There is total loss of availability, resulting in the attacker being able to fully deny access to resources in the impacted component; this loss is either sustained (while the attacker continues to deliver the attack) or persistent (the condition persists even after the attack has completed). Alternatively, the attacker has the ability to deny some availability, but the loss of availability presents a direct, serious consequence to the impacted component (e.g., the attacker cannot disrupt existing connections, but can prevent new connections; the attacker can repeatedly exploit a vulnerability that, in each instance of a successful attack, leaks a only small amount of memory, but after repeated exploitation causes a service to become completely unavailable).

Definitions: FIRST CVSS v3.1 specification.

Exploitation evidence

Disclosed: evidence found.
CVE published 6 May 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors

A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.

Disclosed: The CVE record is public on cve.org. Its publication is t = 0.
Detectable: A public nuclei template can find exposed instances, for defenders and attackers alike.
Weaponised: Public exploit code exists in Metasploit or Exploit-DB, or CISA SSVC or the CVSS exploit maturity reports a public proof of concept.
Exploited in the wild: CISA KEV lists it, CISA SSVC rates exploitation active, or a source reports attacks.
Observed by OffSeq Mirage: OffSeq Mirage honeypot sensors recorded attack traffic for this CVE, or found exposed hosts without attack traffic.

Moments are spaced evenly, not to scale; a dashed line marks a gap of six months or more. Deltas count from t = 0. Sources that give only a date (CISA KEV, Exploit-DB, or a time of exactly 00:00Z) read “same day” rather than hours. Metasploit modules carry the flaw’s disclosure date, not their release date, and nuclei templates carry no date, so both appear above but not on the timeline.

ghsa-m67f-9cj9-483j

What to do

AI-suggested

A fix has been implemented in the Linux kernel that replaces pci_dev_is_disconnected() with pci_device_is_present() to determine when to skip ATS invalidation. This fix improves system stability with negligible performance cost. Users should apply the official kernel update containing this patch to remediate the issue.

Description

CVE-2026-43130 is a medium severity vulnerability in the Linux kernel's iommu/vt-d subsystem. It involves improper flushing of dev-IOTLB when a PCIe device is inaccessible due to link faults, which can cause a system hard-lock. The issue occurs because the kernel incorrectly relies on pci_dev_is_disconnected() to skip ATS invalidation, which does not cover link-down faults. This can lead to a hard lockup during resource release operations such as when a VM fails to connect to a PCIe device and is forcibly destroyed. The fix involves using pci_device_is_present() instead, improving system stability with minimal performance impact.

Impact

The vulnerability can cause a system hard-lock (denial of service) when PCIe devices become inaccessible due to link faults, particularly affecting virtual machine operations that interact with PCIe devices. There is no impact on confidentiality or integrity, but availability is severely affected due to hard lockups.

Summary

The vulnerability in the Linux kernel's iommu/vt-d code arises from flushing the dev-IOTLB only when the PCIe device is accessible in scalable mode. The previous logic used pci_dev_is_disconnected() to skip ATS invalidation for safely removed devices, but this function does not detect link-down caused by faults, leading to potential system hard-locks. This manifests, for example, when a VM fails to connect to a PCIe device and 'virsh destroy' is executed, causing a hard lockup during group file descriptor release. The patch replaces pci_dev_is_disconnected() with pci_device_is_present(), which is slightly slower but more accurate and called only in infrequent paths, thus enhancing system stability especially under high load conditions.

References

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